LG G8000 Service Manual Trouble Shooting
- 89 -
6. TROUBLE SHOOTING
Figure. 6-1 shows a measurement set-up.
Figure 6-1. Measurement set-up
6. TROUBLE SHOOTING
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TOP & BOTTOM
Fig 6-2
Fig 6-3
6. TROUBLE SHOOTING
SW101
N101
FL103
U102
D101
FL101
U105
U101
FL101
FL104
FL105
6.1 Rx Trouble (EGSM)
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6. TROUBLE SHOOTING
Check FL105 or Peripheral circuit
FL103 pin 2 RF signal
is over -63dBm
Check FL103 or Peripheral circuit
FL105 pin 4, 6 RF signal
is over -66dBm
FL101 pin 3 LO signal
is over -23dBm
FL102 pin 5, 7 LO signal
is over -26dBm
Check FL101 or Peripheral circuit
Check FL102 or Peripheral circuit
Rework Calibration
(Over G_MAGIC 170)
Sector Power -85dBm
U105 18, 19, 20, 21
I/Q signal is over 60mV
Check U105
NO
NO
NO
NO
NO
NO
(High Frequency Probe)
@ 947.4MHz
YES
YES
YES
YES
@ 947.4MHz
@ 1854.8MHz
YES
R501, R502, R505, R506
I/Q signal is over 60mV
Check R501, R502, R505, R506
or Peripheral circuit
(Oscilloscope)
@ 1854.8MHz
Set up Test with CalMon
(62CH, Sector Power-60dB, AGC 24dB
FL103 : Antenna S/W
FL105 : Rx SAW Filter
FL102 : Balun
FL101 : Dual VCO
U105 : RF Main Chip
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6.2 Rx Trouble (DCS)
6. TROUBLE SHOOTING
FL103 pin 6 RF signal
is over -63dBm
FL104 pin 4, 6 RF signal
is over -63dBm
FL101 pin 4 LO signal
is over -23dBm
FL102 pin 5, 7 LO signal
is over -26dBm
Check FL103 or Peripheral circuit
Check FL104 or Peripheral circuit
Check FL101 or Peripheral circuit
Check FL102 or Peripheral circuit
FL102
Rework Calibration
(Over G_MAGIC 170)
Sector Power -85dBm
U105 pin 18, 19, 20, 21
I/Q signal is over 60mV
Check U105
NO
NO
NO
NO
(High Frequency Probe)
@ 1842.8MHz
YES
YES
NO
YES
YES
@ 921.4MHz
YES
R501, R502, R505, R506
I/Q signal is over 60mV
Check R501, R502, R505, R506
or Peripheral circuit
NO
YES
(Oscilloscope)
@ 1842.8MHz
@ 921.4MHz
Setup Test with CalMon
(700CH, Sector Power -60dBm, AGC 24dB)
FL103 : Antenna S/W
FL105 : Rx SAW Filter
FL102 : Balun
FL101 : Dual VCO
U105 : RF Main Chip
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